Merging statistics and geospatial information, 2012 projects - Slovenia
The Statistical Office of the Republic of Slovenia (SURS) managed a large number of datasets which were disseminated over a variety of different platforms (including cartographic presentations) with the lack of any coherent and integrated system for the dissemination of geospatial statistics.
The objectives of this project were to:
- improve the integration of geo-information and geo-referencing within the statistical production process;
- illustrate how linking geo- and statistical information provides additional value and creates new information;
- design innovative web applications to show the spatial distribution of statistics.
The statistical office worked with the Geodetic Institute of Slovenia, which provided access to information technology (IT) staff with knowledge in software development to develop an application. The institute is the leading Slovene public institution for geodetic, cartographic, geo-informatic and hydrographic research and development and is a part of the national geodetic service. Furthermore, it already had experience implementing INSPIRE.
The Register of Spatial Units is the main source of administrative geospatial data in Slovenia. It contains over 40 administrative and non-administrative official territorial divisions of Slovenia and is currently managed by the Surveying and Mapping Authority of the Republic of Slovenia (GURS). In 2008, a project introduced square grid vector layers with seven basic grids (grids ranged from 100 m * 100 m to 10 km * 10 km).
As a part of this project, the statistical office reviewed the statistical data that were already available through interactive cartographic visualisations, in order to identify: whether the data were relevant; whether other data should/could be added at least at a regional level; whether some data could be presented for grids; whether there were confidentiality issues.
Having identified those data sets that could be geocoded a number of sources were identified together with areas where they could be improved. For example, information on motor vehicle ownership in the Central Register of Motor Vehicles and Trailers was linked to the Central Population Register or the Business Register in order to have more accurate ownership addresses, before disseminating these data. Other datasets that were assessed included the Statistical Register of Employment and various datasets related to income. A number of organisations producing official statistics outside of the statistical office were also involved, for example the National Institute of Public Health which had data on standardised mortality rates and information for physicians.
Although all statistical data were either geocoded or geo-referenced throughout the entire statistical production process, the Slovenian statistical office did not have a permanent solution regarding the production of geospatial statistical data for dissemination purposes. The project addressed this issue through the design and development of a web application — STAGE (Statistics & Geography) — as a central dissemination tool for geospatial statistics. As well as bringing together statistical data, the development of STAGE was an opportunity to implement INSPIRE’s metadata rules. STAGE replaced two Flash based applications (ISAS and KASPeR).
The project also considered confidentiality: prior to the 2011 census, the standard geospatial units for the dissemination of official statistics were administrative units — the smallest being settlements; grids were produced only upon request and each request was discussed by the Data Protection Committee. The statistical office performed many analyses in order to define the confidentiality rules that should be applied to grid statistics in Slovenia. It was decided that information on education and economic activity should be subject to disclosure control, whereas other information could be published without any controls for disclosure, such as the size of the population by age group and sex, the number of households and dwellings by size or the number of buildings by year of construction.
This project resulted in the development of an integrated system for the dissemination of geospatial statistical data in STAGE. STAGE is an interactive web application for cartographic visualisation of geospatial statistics and downloading data: it displays data in the form of choropleth maps. It is designed as an INSPIRE compliant application. The merging of geospatial information and geocoded statistical data was significantly simplified through the development of STAGE. Official geospatial statistical data can now be integrated into the data infrastructures used by other major data providers or simply combined with user’s own geospatial datasets to create additional added value. A list of variables was identified for which statistical data are now published on a regular basis in STAGE.
The implementation of STAGE opened a new dimension for the dissemination of official statistics in Slovenia. Many public agencies are following the idea of presenting their data through grid-based maps.
The quality of data in some of the source databases was also improved through this project when checking data prior to its use in STAGE.
Awareness of the importance of the spatial dimension of statistical data was also increased within the national statistical office.